Mauna Kea

Mauna Kea is a 13803 foot (4200 meter) dormant volcano on the island of Hawaii. A number of observatories are located on or near its summit. The atmosphere is very dry, unpolluted and cloud cover is generally below the summit. It is also distant from cities. The University of Hawaii built Mauna Kea's the first modern observatory with a 2.2-meter telescope in 1970. The land devoted to observatories is currently managed by the University of Hawaii as the Mauna Kea Observatories. Some current observatories:

• Canada-France-Hawaii Telescope (CFHT) - 3.58-meter visible/infrared.
• Gemini North (Gemini Observatory) - 8.1-meter visible/infrared.
• IRTF - 3.0-meter infrared.
• James Clerk Maxwell Telescope (JCMT) - 15-meter submillimeter.
• Subaru Telescope - 8.2-meter visible/infrared.
• Submillimeter Array (SMA) - array of 6-meter radio telescopes.
• United Kingdom Infrared Telescope (UKIRT) - 3.8-meter infrared.
• UH88 - 2.2-meter visible/infrared.
• VLBA MK (VLBA) - 25-meter radio.
• Keck Observatory - 2 10-meter visible/infrared.

Former:

• UH Hilo Hoku Ke'a - 0.9-meter visible.
• Caltech Submillimeter Observatory (CSO) - 10.4-meter submillimeter.

Planned:

• Thirty Meter Telescope (TMT).

There is concern that the mountain is overrun by telescopes, and the current plan is to decommission some: CSO and Hoku Ke'a have been removed and UKIRT is slated for future removal.

The Hawaiian Islands, which feature tall mountain peaks with dry air and dark sky, also host observatories on Mauna Loa (Mauna Loa Solar Observatory), also on the island of Hawaii, and on Haleakala (Haleakala Observatory) on the island of Maui. Among them, Mauna Kea has the highest altitude and best atmospheric conditions for observation.